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United States Patent |
6,227,694
|
Mitake
,   et al.
|
May 8, 2001
|
High speed collision reaction method
Abstract
Two or more substances are flowed from different inflow passages, and
collided against each other at a flow rate of 4 m/sec or higher to cause a
uniform reaction with each other for a short time. This method is
advantageous for producing a dispersion liquid containing very fine
particles the size of submicrons.
Inventors:
|
Mitake; Kazutoshi (Itabashi-ku, JP);
Miyake; Fuminori (Itabashi-ku, JP);
Yasuda; Fumio (Itabashi-ku, JP);
Yazaki; Tatsuo (Osaka, JP);
Toda; Megumu (Osaka, JP)
|
Assignee:
|
Genus Corporation (Tokyo-to, JP);
Hakusui Tech Co., Ltd. (Osaka-fu, JP)
|
Appl. No.:
|
995694 |
Filed:
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December 22, 1997 |
Foreign Application Priority Data
| Dec 27, 1996[JP] | 8-351502 |
| Mar 24, 1997[JP] | 9-070154 |
Current U.S. Class: |
366/162.4; 366/173.1 |
Intern'l Class: |
B01F 015/02 |
Field of Search: |
366/162.4,173.1
261/18.1,40
422/131,135,140,142,145,149,156
|
References Cited
U.S. Patent Documents
2751335 | Jun., 1956 | Carver et al. | 366/162.
|
3190846 | Jun., 1965 | Lipton et al. | 366/173.
|
3306342 | Feb., 1967 | Savlo et al. | 366/173.
|
3410531 | Nov., 1968 | Baker | 366/162.
|
3692283 | Sep., 1972 | Sauer et al. | 366/173.
|
3833718 | Sep., 1974 | Reed | 366/162.
|
3847375 | Nov., 1974 | Kuerten et al. | 366/167.
|
3849074 | Nov., 1974 | Ficklinger et al. | 366/162.
|
4043486 | Aug., 1977 | Wisbey | 366/162.
|
4289732 | Sep., 1981 | Bauer et al. | 366/162.
|
4378335 | Mar., 1983 | Boden et al. | 366/162.
|
4440320 | Apr., 1984 | Wernicke | 366/162.
|
4474310 | Oct., 1984 | Muller et al. | 366/162.
|
4523696 | Jun., 1985 | Commette et al. | 366/162.
|
4568003 | Feb., 1986 | Sperry et al. | 366/162.
|
4595565 | Jun., 1986 | Tenhagen | 366/162.
|
4773564 | Sep., 1988 | Wallner | 366/162.
|
4854713 | Aug., 1989 | Soechtig | 366/162.
|
4876071 | Oct., 1989 | Toda et al. | 366/162.
|
5181987 | Jan., 1993 | Breuker et al. | 366/162.
|
5223550 | Jun., 1993 | Hughes et al.
| |
5246673 | Sep., 1993 | Hed.
| |
5312596 | May., 1994 | Proksa et al. | 366/162.
|
5380089 | Jan., 1995 | Karasawa | 366/162.
|
5562883 | Oct., 1996 | Salisbury et al. | 366/173.
|
Foreign Patent Documents |
3633343 | Mar., 1988 | DE.
| |
0344898 | Dec., 1989 | EP.
| |
63-278534 | Nov., 1988 | JP.
| |
4-139441 | May., 1992 | JP.
| |
WO 8809208 | Dec., 1988 | WO.
| |
WO 9407582 | Apr., 1994 | WO.
| |
Other References
Patent Abstracts Of Japan, vol. 013, No. 105 (C-575), Mar. 13, 1989 & JP 63
278534 A (Nordson KK), Nov. 16, 1988.
Patent Abstracts Of Japan, vol. 015, No. 012 (C-0795), Jan. 10, 1991 & JP
02 261525 A (Cosmo Keiso KK), Oct. 24, 1990.
|
Primary Examiner: Soohoo; Tony G.
Attorney, Agent or Firm: Jordan and Hamburg LLP
Claims
What is claimed is:
1. A method of producing a substance of fine particles comprising:
introducing first and second inorganic reactants each dissolved in a
solvent into respective first and second longitudinally extending colinear
path each having path-defining boundaries and each having a substantially
equal and constant traverse cross sectional area along the longitudinal
thereof;
flowing said first and second reactants substantially colinearly along said
first and second colinear path respectively toward a collision enclosure
having an enclosure-defining boundary which is co-extensive and colinear
with said path-defining boundaries such that the traverse cross sectional
area of said enclosure defining boundary is substantially equal to said
traverse cross sectional area of said path-defining boundaries;
ejecting said first and said reactants into said reactants into said
collision enclosure;
colliding said first and second reactants head on within said collision
enclosure;
effecting a substantially instantaneously chemical reaction between said
first and second reactants in said collision enclosure as a result of said
head-on collision;
producing a substance of fine particles in said collision enclosure as a
result of said reaction in said collision enclosure;
substantially immediately after producing said collision substance
conducting said substance from said collision enclosure into a
longitudinally extending outlet path having a path-defining boundary in
which the outlet path extends laterally of said first and second colinear
paths; and
effecting the aforesaid steps continually and non-cyclically.
2. A method according to claim 1, wherein the speed at which said reactants
collide is 4 m/sec or higher.
3. A method according to claim 1, wherein the speed at which said reactants
collide is 7 m/sec or higher.
4. A method according to claim 1, further comprising the step of adding a
dispersing agent before the collision reaction.
5. A method according to claim 1, further comprising the step of adding a
dispersing agent after the collision reaction.
6. A method according to claim 1, further comprising the step of adding a
dispersing agent before and after the collision reaction.
7. A method according to claim 1 further comprising reducing the average
particle size of said substance by throttling said substance as said
substance is removed from said collision enclosure.
8. A method according to claim 1 further comprising introducing a third
reactant into said collision enclosure along a third linear path, said
third linear path being perpendicular to said colinear first and second
paths, and introducing a fourth reactant into said collision enclosure
along a fourth linear path, said fourth linear path being perpendicular to
said colinear first and second paths.
9. A method according to claim 1 wherein said substance is a first
substance, and further comprising conducting said first substance along
said outlet path to a second collision enclosure, directing a third
reactant to said second collision enclosure, colliding said third reactant
and said first substance in said second collision enclosure, effecting a
further reaction between said third reactant and said first substance in
said second collision enclosure to obtain a second substance of fine
particles, and directing said second substance from said second collision
enclosure.
10. A method according to claim 1 where said step of ejecting a first
reactant into said collision enclosure comprises ejecting a first liquid
reactant into said collision enclosure at a first flow rate, said step of
ejecting a second reactant into said collision enclosure comprising
ejecting a second liquid reactant into said collision enclosure at a
second flow rate, said step of conducting said substance from the
collision enclosure comprising removing a liquid substance from the
collision enclosure at a flow rate substantially equal to the sum of said
first and second flow rates.
11. A method according to claim 1 wherein said outlet path extends
substantial perpendicular relative to said first and second colinear
paths.
12. A method according to claim 1 wherein said collision enclosure is a
generally T-shaped collision enclosure.
13. The method of claim 1 wherein:
said at least one reactant includes an inorganic compound dissolved in a
specified solvent; and
said at least one other reactant includes a second inorganic compound
dissolved in a specified solvent.
14. A method according to claim 1 wherein the solvent in which said first
reactant is dissolved is different from the solvent in which said second
reactant is dissolved.
15. A method according to claim 1 wherein the solvent in which said first
reactant is dissolved is the same as the solvent in which said second
reactant is dissolved.
16. A method according to claim 1 wherein said substance of fine particles
is insoluble in the solvent in which the first and second reactants are
dissolved.
17. A method according to claim 1 wherein said step of producing said
substance of fine particles comprises producing fine particles having an
average particle diameter of about 1.0 .mu.m or smaller.
18. A method according to claim 1 wherein said step of producing said
substance of fine particles comprises producing fine particles having an
average particle diameter of about 0.5 .mu.m or smaller.
19. A method according to claim 1 wherein said step of producing said
substance of fine particles comprises producing fine particles having an
average particle diameter of about 0.2 .mu.m or smaller.
20. A method of reacting two or more reactants to produce a reactant
product of fine particles comprising:
introducing flowing materials along first, second, third and fourth inlet
passages respectively into a collision enclosure, at least two of said
flowing materials being inorganic reactants dissolved in a solvent;
effecting a head-on collision between said at least two introduced
reactants within said collision enclosure;
effecting a substantially instantaneous chemical reaction between said at
least two introduced reactants to produce a reaction product of fine
particles;
substantially immediately removing the reaction product from the collision
enclosure via an outlet passage; and
effecting said introducing step and said removing step continuously and
non-cyclically.
21. A method according to claim 20 wherein said first and third flowing
materials are substantially the same and said second and fourth flowing
materials are substantially the same.
22. A method according to claim 20 wherein said first to fourth reactants
are different from one another.
23. A method of reacting two or more reactants comprising directing a first
reactant along a first linear path to a collision enclosure, directing a
second reactant along a second linear path to said collision enclosure,
said first and second linear paths being substantially colinear, directing
a third reactant to said collision enclosure along a third linear path,
said third linear path being perpendicular to said colinear path,
directing a fourth reactant to said collision enclosure along a fourth
linear path, said fourth linear path being perpendicular to said colinear
path, said first and third reactants being the same and said second and
fourth reactants being the same, colliding said first and second reactants
and said third and fourth reactants in said collision enclosure, effecting
a reaction between said first and second reactants and between said third
and fourth reactants during said colliding of said first and second
reactants and said third and fourth reactants in said collision enclosure
to obtain a reaction product, directing said reaction product from said
collision enclosure, and effecting the aforesaid steps continuously and
non-cyclically to produce the reaction product continuously and
non-cyclically.
24. A method of producing a reaction product of final particles comprising:
introducing first and second inorganic reactants each dissolved in a
solvent into respective first and second longitudinally extending colinear
passages each having passage-defining boundaries formed by passage walls,
flowing said first and second reactants substantially colinearly along said
first and second colinear passages respectively at a flow rate of 4 m/sec
or higher toward a collision enclosure having an enclosure-defining
boundary which is co-extensive and colinear with said passage-defining
boundaries;
ejecting said first and second reactants into said collision enclosure at a
flow rate of 4 m/sec or higher;
effecting a head-on collision of said colinearly flowing first and second
reactants within said co-extensive and colinear enclosure-defining
boundary of said collision enclosure;
effecting a substantially instantaneously chemical reaction between said
first and second reactants in said collision enclosure as a result of said
head-on collision;
producing a reaction product of fine particles having an average partials
size of 1.0 .mu.m or less in said collision enclosure as a result of said
reaction in said collision enclosure;
substantially immediately after producing said reaction-product conducting
said reaction product from said collision enclosure into a longitudinally
extending outlet path having a path-defining boundary in which the outlet
path extends laterally of said first and second colinear passages; and
effecting the aforesaid steps continually and non-cyclically.
25. A method according to claim 24 wherein said substance is a first
substance, further comprising directing said first substance to a second
collision enclosure, directing a third reactant to said second collision
enclosure, effecting a reaction between said first substance and said
third reactant during said colliding in said second collision enclosure to
obtain a second substance of fine particles, and directing said second
substance from said second collision enclosure.
26. A method according to claim 24 further comprising reducing the particle
size of said reaction product by throttling said reaction product as the
reaction product flows in said outlet path.
27. A method according to claim 24 further comprising reducing the particle
size of said reaction product by increasing the flow rate of said first
and second reactants in said respective first and second passages.
28. A method of reacting two or more reactants comprising directing a first
organic reactant dissolved in a solvent along a first linear path to a
collision enclosure, directing a second organic reactant dissolved in a
solvent along a second linear path to said collision enclosure, said first
and second linear paths being substantially colinear, directing a third
organic reactant dissolved in a solvent to said collision enclosure along
a third linear path, said third linear path being perpendicular to said
colinear path, directing a fourth organic reactant dissolved in a solvent
to said collision enclosure along a fourth linear path, said fourth linear
path being perpendicular to said colinear path, said first and third
reactants being the same and said second and fourth reactants being the
same, colliding said first and second reactants head-on and said third and
fourth reactants head-on in said collision enclosure, effecting a chemical
reaction between said first and second reactants and between said third
and fourth reactants during said head-on colliding of said first and
second reactants and said third and fourth reactants in said collision
enclosure to obtain a reaction product, directing said reaction product
from said collision enclosure, and effecting the aforesaid steps
continuously and non-cyclically to produce the reaction product
continuously and non-cyclically.
Description
BACKGROUND OF THE INVENTION
This invention relates to a high speed collision reaction method for
causing a chemical reaction between two kinds of substance by high speed
collision.
To mix and react two or more reactive substances, there has been known a
method which uses a batch-type reactor including an agitation chamber. In
this method, two or more substances are supplied into the agitation
chamber simultaneously or successively, and are reacted with each other by
agitation in the agitation chamber. Also, there has been known a method
which uses a reactor including an agitation flow passage, such as a static
mixer. The agitation flow passage is provided with blades therein to cause
turbulence. In this method, two or more substances are flowed in the
agitation flow passage, and are reacted with each other by agitation in
the agitation flow passage.
In the method using a batch-type reactor, two or more substances are
supplied from different sources into a fixed volume agitation chamber
simultaneously or successively, and are agitated for a specified time to
cause a reaction between the substances. When the reaction is completed or
reaches an equilibrium state, a product is removed. However, this method
has the following problems. If a state change occurs in a reaction system,
e.g., the viscosity of the reactive substance increases or the substances
are not agitated uniformly, the reaction efficiency consequently
decreases. Also, if an unmixable part is created and remains in a reaction
system for a long time, the unmixable part aggregates into a considerable
mass, thus making it difficult to produce a finely dispersed mixture.
Further, keeping the reaction system in the fixed chamber for a long time
inevitably causes changes in the physical and chemical conditions. For
example, the amount, concentration, and pH of reactive substances will
vary over time. It is very difficult to maintain the reaction system at
constant conditions. In the batch-type reaction method, in principle, the
reaction is conducted per batch. To improve this drawback, there has been
proposed a reactor system in which a plurality of agitation chambers are
connected in series to perform a continuous reaction. In this case,
however, the concentration of reactive substances changes as they travel
from an initial chamber to a final chamber. Usually, the concentration
decreases toward the final chamber. Accordingly, the reaction efficiency
decreases toward the final chamber. Thus, it has been very difficult to
attain the required reaction efficiency.
On the other hand, the method using the agitation flow passage also has the
following problems. In this method, blades or other special elements are
provided in the agitation flow passage to forcibly generate turbulence. A
primary substance is flowed in a direction or circulated in the agitation
flow passage while it is in a state of turbulence. A secondary substance
is joined to the flow of the primary substance to cause a reaction between
the substances. However, contact between the primary substance and the
secondary substance inevitably occurs before the secondary substance
enters the region of turbulence, consequently causing a heterogeneous
reaction for a short time. Further, even if two or more substances come
into contact at the same time to cause a homogeneous reaction, a high
reaction efficiency cannot be attained.
There has been known another method which uses an ejector. In this method,
a large flow of primary substance is produced. A secondary substance is
ejected into the large flow of primary substance at a high speed to react
with the primary substance. However, this method is not suitable when the
substances have a high viscosity or when the reaction product has a high
viscosity. Further, the control of substance mixing proportion is very
difficult. Accordingly, this method cannot be applied in other than a
limited field.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a high speed collision
reaction method which has overcome the problems in the prior art.
According to an aspect of the present invention, a method for causing a
reaction between two or more reactive substances comprises the step of
colliding a flow of one reactive substance against a flow of another
reactive substance at a high flow rate to cause a reaction between them.
In this method, the flows of reactive substances are collided against each
other at a high speed to cause a reaction. Accordingly, very fine
particles can be produced more efficiently. Also, since the reaction is
attained for a very short time, the conditions for the reaction can be
controlled more easily.
The above and other objects, features and advantages of the present
invention will become more apparent upon a reading of the following
detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view showing a high speed collision reactor embodying
the present invention;
FIG. 2 is a sectional view taken along the line II--II in FIG. 1;
FIG. 3 is a sectional view taken along the line III--III in FIG. 1;
FIG. 4 is a sectional view taken along the line IV--IV in FIG. 2;
FIG. 5 is a conceptual diagram illustrating a first high speed collision
reaction manner embodying the present invention;
FIG. 6 is a graph illustrating a relationship between the colliding flow
rate and the average diameter of produced particles;
FIG. 7 is a conceptual diagram illustrating a flow control conducted for
produced particles;
FIG. 8 is a conceptual diagram illustrating another flow control conducted
for produced particles;
FIG. 9 is a conceptual diagram illustrating still another flow control
conducted for produced particles;
FIG. 10 is a conceptual diagram illustrating a second high speed collision
reaction manner embodying the present invention;
FIG. 11 is a conceptual diagram illustrating a third high speed collision
reaction manner embodying the present invention;
FIG. 12 is a conceptual diagram illustrating a fourth high speed collision
reaction manner embodying the present invention;
FIG. 13 is a conceptual diagram illustrating a fifth high speed collision
reaction manner embodying the present invention;
FIG. 14 is a conceptual diagram illustrating a sixth high speed collision
reaction manner embodying the present invention;
FIG. 15 is a conceptual diagram showing a first combination of a high speed
collision reaction and an emulsion dispersion;
FIG. 16 is a conceptual diagram illustrating a seventh high speed collision
reaction manner embodying the present invention;
FIG. 17 is a conceptual diagram illustrating a second combination of a high
speed collision reaction and an emulsion dispersion;
FIG. 18 is a conceptual diagram illustrating an eighth high speed collision
reaction manner embodying the present invention;
FIG. 19 is a conceptual diagram illustrating a third combination of a high
speed collision reaction and an emulsion dispersion; and
FIG. 20 is a conceptual diagram illustrating a fourth combination of a high
speed collision reaction and an emulsion dispersion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE PRESENT INVENTION
According to the present invention, flows of two or more substances in the
form of liquid and/or gas having a reactivity with each other are joined
in such a way that substances collide with each other at a high speed to
react with each other.
FIGS. 1 to 4 show a reactor embodying the present invention. This reactor
is configured so as to permit collision reaction between two substances.
FIG. 1 is a top plan view of the reactor, FIG. 2 being a sectional view
along the line II--II in FIG. 1, FIG. 3 being a sectional view along the
line III--III in FIG. 1, and FIG. 4 being a sectional view along the line
IV--IV in FIG. 2. This reactor includes two rectangular blocks 1a and 1b
which are assembled into one body by being fastened with four bolts 2 at
their respective four corners. The upper block 1a is provided with two
inlet members 3a and 3b, and an outlet member 4. The inlet members 3a and
3b are respectively formed with inflow passages 5a and 5b which
communicate by channels 6a and 6b. The channels 6a and 6b, as shown in
FIG. 4, extend in opposite directions. From a joining portion 7 of the
channels 6a and 6b extends a channel 8 in a perpendicular direction to the
channels 6a and 6b. The channel 8 communicates with an outflow passage 9
formed in the outlet member 4. Accordingly, flows of the two substances
passing through the channels 6a and 6b collidingly meet each other at the
joining portion 7 where reaction occurs. A product C of the reaction flows
through the channel 8, as shown in FIG. 5, and the outflow passage 9 to a
reservoir arranged outside of the reactor.
Specifically, reactant A and reactant B are respectively supplied into the
inflow passages 5a and 5b at a high speed or high pressure, and flow to
the joining portion 7 through the channels 6a and 6b. The fluids A and B
collide at a flow rate of a jet. In the small space of the joining portion
7, the jet flows of the fluids A and B collide with each other at high
speed. Also, furious turbulence and cavitation occur in the small space of
the joining portion 7. Further, the fluids A and B collide against an
inner wall of the joining portion 7. Accordingly, the fluids A and B are
mixed at a high kinetic energy, thus causing reaction between the fluids A
and B in a very short time. FIG. 5 conceptually shows this high speed
collision reaction.
In this high speed collision reaction, the reaction rate and reaction state
between the two fluids A and B can be easily controlled in accordance with
characteristics of the fluids by adjusting the respective flow rates or
kinetic energy of the fluids A and B. Also, the respective supply amounts
or proportion of the fluids A and B can be easily controlled by providing
supply devices (pumps) for the fluids A and B, respectively.
In this high speed collision reaction, the flow rate of the reactant is
important. Specifically, it is desirable to flow fluids at a rate of 4
m/sec or higher, and preferably 7 m/sec or higher, and more preferably 15
m/sec or higher. Such high speed collision reaction makes it possible to
produce fine particles the size of submicrons which cannot be produced in
the conventional methods.
Further, it may be desirable to suppress or prevent fine particles from
aggregating after the reaction, for example, by agitating the fine
particles in a large amount of liquid for a short time.
FIG. 6 is a graph illustrating a relationship between the flow rate and the
average particle diameter. The relationship was obtained in an example
where barium chloride and sodium sulfate were collided at a high speed and
reacted with each other in the reactor shown in FIGS. 1 to 4, thereby
producing barium sulfate. The reaction was conducted at a number of flow
rates, and an average particle diameter of resultant barium sulfate at
each flow rate was obtained. When the flow rate in the collision reaction
is set at 4 m/sec or higher, the average particle diameter was about 1.0
.mu.m or smaller. When the flow rate was set at 7 m/sec or higher, the
average particle diameter was about 0.5 .mu.m or smaller. When the flow
rate was set at 15 m/sec or higher, the average particle diameter was
about 0.2 .mu.m or smaller. From these results, it can be found that the
high speed collision reaction of the present invention can produce
remarkably fine particles.
On the other hand, the conventional method of reacting two or more
substances using jet flows of 1 to 3 m/sec can produce particles not
smaller than 3 .mu.m.
As described above, the high speed collision reaction of the present
invention can produce very fine particles the size of submicrons or
dispersions including very fine particles. Further, it is possible to add
a proper amount of a dispersing agent in a reaction system to prevent
secondary agglutination after reaction. In this way, a stable dispersion
with very fine particles dispersed therein, which has an appearance
similar to an emulsion or a solution, can be obtained.
The flow rate-particle diameter relationship shown in FIG. 6 refers to the
production of barium sulfate fine particles from barium chloride and
sodium sulfate. Although the diameter of the produced particle slightly
varies depending on the reactants, the relationship between the flow rate
of the reactants and the diameter of the produced particles is applicable
for various kinds of substances. In other words, the diameter of the
produced particle noticeably changes above and below the flow rate of 4
m/sec. It has been confirmed that very fine particles, which cannot be
produced by conventional methods, can be obtained by colliding material
fluids at a flow rate of 4 m/sec or higher.
Accordingly, a feature of the method of the present invention is that the
flow rate for the collision reaction of two or more substances is 4 m/sec
or higher, preferably 7 m/sec or higher, and more preferably 15 m/sec or
higher. The reactor shown in FIGS. 1 to 4 is only an exemplary reactor,
and the method of the present invention is not limited to the use of the
reactor shown in FIGS. 1 to 4. Any reactor can be used as long as it has
such a construction that two or more substances collide at the
above-mentioned high speeds to react them in a very short time, and
discharge produced particles. As long as such conditions are satisfied,
various modifications can be made to the number and the size of inflow
passages, the joining direction of reactants, the shape and structure of
the joining portion, and the direction of the outflow passage.
However, the reactor shown in FIGS. 1 to 4 is preferable for the method of
the present invention because the construction is very simple and the
design and production are thus easy. Specifically, the reactor includes
the upper and lower blocks 1a and 1b. The upper block 1a is formed with
the inflow passages 5a, 5b, and the outflow passage 9. The lower block 1b
is formed with the inflow channels 6a and 6b, the joining portion 7, and
the outflow channel 8. Accordingly, the number of inflow passages and
channels can be easily changed in accordance with the number of reactants.
The inflow channels 6a and 6b, the joining portion 7, and the outflow
channel 8 may be formed in the upper block 1a instead of the lower block
1b, or may be formed in both the upper block 1a and the lower block 1b.
Although the feature of the method of the present invention is that two or
more substances are squarely collided against each other along
substantially a straight line at high speed, the construction of the
outflow of the reaction product is not limited to the specific model, but
may be modified into various arrangements. For example, as shown in FIGS.
7 to 9, a reaction product C may be passed through another arrangement in
accordance with the characteristics of the reaction product C. To further
reduce the size of the reaction product C or to make finer particles, a
throttling portion 8 may be formed at an immediate downstream location of
the joining portion 7 as shown in FIG. 7, or at a downstream location
slightly away from the joining portion 7 as shown in FIG. 8. Also, it may
be appreciated, as shown in FIG. 9, to broaden the outflow channel
downstream of the joining portion 7 to reduce the pressure of the
downstream side, and thereby enhance the collision reaction and make the
flow of reaction product C smoother.
Furthermore, according to the present invention, there may be various
modification of the high speed collision reaction as follows.
As shown in FIG. 10, two reactants A and B collide in two opposite
directions at the same time at a high speed.
As shown in FIG. 11, four reactants A to D collide in two opposite
directions at the same time at a high speed.
As shown in FIGS. 12 and 13, two reactants A and B collide by ejecting them
from oppositely arranged slit nozzles at a high speed.
As shown in FIG. 14, while a reactant A is flowed in a specified direction
at a high rate of speed, four reactants B, C, D, and E are directed to the
flow of the substance A at a high flow rate. In this case, the flows of
the substances B and C, and the flows of the substances D and E face each
other.
As shown in FIG. 16, reactants A and B are respectively branched into two
flow paths and collide at two points. After that, the reaction product
collides again in a downstream and then is discharged in a single path.
As shown in FIG. 18, reactants A and C, and reactants B and D are
respectively collided against each other at different positions.
Thereafter, reaction product AC and reaction product BD are respectively
branched into two flow paths, and collided against each other at two
different points. Reaction product ABCD is collided against each other
more downstream, and then discharged in a single flow path.
In the reaction manner shown in FIG. 14, the substance A may be a reaction
medium, and the substances D and E may be primary substances. Prior to
collision, reaction between the substances D and E using the substance A
as a reaction medium, the substances B and C, such as a surface active
agent (dispersing agent etc.), reaction accelerator, reaction auxiliary
agent, or catalyst may be added and dispersed in the flow of the substance
A. Alternatively, the substance A may be a reaction medium, and the
substances B and C may be primary reactants. The substances D and E may be
a reaction shortstop agent, a secondary reactive substance, a finishing
agent, or a modifier and the like, and may be added downstream of the
reaction of the substances B and C.
Such addition can be applied for the reaction manner shown in FIG. 16. More
specifically, prior to the collision reaction between the substances A and
B, substances C and C', such as a surface active agent (dispersing agent
etch), reaction accelerator, reaction auxiliary agent, or catalyst may be
added to the substances A and B, respectively. Alternatively, a substance
D, such as a reaction shortstop agent, secondary reactive substance,
finishing agent, or modifier may be added to the reaction product of A and
B.
Also, such addition can be applied for the reaction manner shown in FIG.
18. More specifically, prior to the collision reaction between substances
A and B, substances C and D, such as a surface active agent (dispersing
agent etc.), reaction accelerator, reaction auxiliary agent, or catalyst
may be added to the flows of the substances A and 5, respectively. In
addition, during the collision reaction between the reaction products AC
and BD, substances E and F, such as a surface active agent (dispersing
agent etc.), reaction accelerator, reaction auxiliary agent, or catalyst
may be added to the flows of the substances AC and BD, respectively.
Further, substances G and H, such as a reaction shortstop agent, secondary
reactive substance, finishing agent, or modifier may be added to the flow
of the reaction product.
Furthermore, as shown in FIGS. 15, 17, and 19, a pump P is provided for
pressurizing fluid containing particles of reaction product produced by
the reaction shown in FIGS. 14, 16, and 18, and a dispersing apparatus N,
e.g., a dispersing apparatus disclosed in Japanese Unexamined Patent
Publication No. 9-201522, is provided to thereby increase the stability of
a dispersion containing fine particles.
FIG. 20 shows still another collision reaction of the present invention. A
reaction product of substances A and B is added with a surface active
agent, such as a dispersing agent, a reaction shortstop agent, a second
order substance, a finishing agent, or a modifier upstream and/or
downstream of a pump P. The resultant is introduced into a dispersing
apparatus N. This will more reliably prevent very fine reaction product
particles from agglutinating.
Examples of means of supplying reactants include a plunger pump, snake
pump, diaphragm pump, centrifugal pump, or the like in consideration of
the kind and flowability of substance. Where the reactant is in the form
of a gas or mist, a high pressure pump may be used. The flow rate of
reactants before collision is controlled by adjusting the supplying
pressure of the supply means and the section area of the flow passage.
Also, the pressure of the outflow of reaction product is controlled in a
range of 0.1 to 300 Mpa by adjusting the section area of the outflow
passage.
The flow in the outflow passage is substantially identical to the flow in
the inflow passage where the reactants are liquid. In the case of at least
one reactant being a gas, however, the flow in the outflow passage is
greatly different from or is remarkably smaller than the flow in the
inflow passage, because the gaseous substance converts into the liquid or
solid state after reaction. Accordingly, the supplying pressure and flow
section area are determined in consideration of a phase change after
reaction.
The high speed collision reaction occurs in the joining portion 7 where a
high energy consequently generates. The inner surface of the joining
portion 7 is subjected to severe abrasion. Therefore, the joining portion
7 is required to have a resistance to abrasion. Also, depending on
characteristics of reactants and reaction product, the joining portion 7
is required to have a resistance to acid and alkaline chemicals, to
solvents, and to heat. These requirements are satisfied by forming or
depositing the chemically exposed portion of the joining portion 7 with
durable materials, e.g., cemented carbides such as WC, abrasion-resistant
ceramics such as zircon, alumina, boron carbide, sintered diamond, or
monocrystalline diamond.
The high speed collision reactions of the present invention can be applied
for a wide variety of substances which can be supplied under pressure,
such as liquid substances, solutions, emulsions, suspensions, sol-gel
liquids, gases, or gases containing mists.
As described above, according to the present invention, substances are
collided in the joining portion 7 at a high speed to react with each other
for a very short time. Reaction product is discharged out of the reactor
through the outflow passage 9 without being held in the reaction system
immediately after the reaction. This arrangement is highly advantageous
for producing very fine particles. More specifically, in the conventional
batch-type method and agitation flow passage method, reaction between
substances gradually proceeds. Accordingly, a variation in the reaction
conditions, such as substance concentration, inevitably occurs as time
passes, consequently causing aggregation of substances. On the other hand,
in the method of the present invention, collision and reaction between
substances are made in an extremely small space for a very short time,
thus making it possible to produce very fine particles without forming
aggregations.
Furthermore, in the conventional batch-type method and the agitation flow
passage method, it is difficult to control the temperature of the reaction
system, such as a momentary increase and decrease in temperature, because
the amount of substance residing in the reaction system, the residence
time of substance in the reaction system, and the size and heat capacity
of the reactor vary depending on each case. As a result, increases in
equipment costs and energy costs are inevitable. On the other hand, in the
method of the present invention, collision reaction occurs in an extremely
small space for a very short time. The temperature control of the small
space can be more efficiently conducted by providing a heating device and
a cooling device for the small space, thus assuring uniform reaction.
Moreover, the method of the present invention is very effective where the
reaction product is liable to change its characteristics as the
temperature varies.
In the fine particles fields, such as medicine industries, food industries,
and electronic materials industries, contamination by foreign matters and
bacteria causes serious problems. The method of the present invention
enables instantaneous reaction in a perfect closed space completely
blocked from the atmosphere. Accordingly, the inventive method can more
effectively and easily eliminate this problem by only keeping the
substance supplying system from being contaminated. Also, in the medicine
and food industries, it has been confirmed that a sterilizing effect can
be obtained by application of high pressure. Accordingly, the inventive
method can additionally provide sterilization owing to the high pressure.
In a chemical reaction, the reaction efficiency between a gas and a liquid,
and between a gas, a liquid, and a solid greatly depends on the solubility
of gas in liquid. In other words, the reaction efficiency is increased by
increasing the concentration of gas in liquid. In the inventive method,
the solubility of gas in liquid can be easily increased by supplying
substances under high pressure. This makes it possible to easily increase
the efficiency of a reaction when using a gaseous substance.
The method of the present invention is applicable to a wide variety of
reactions, such as liquid and liquid reaction, gas and liquid reaction, or
gas and gas reaction, by effectively utilizing the above-described
advantageous features of the method in the various industrial fields of
producing medicines, foods, paints, inks, pigments, photosensitive
materials, magnetic recording mediums, and the like. It should be noted
that in the present invention, the term "liquid" includes not only a
substance in the form of liquid, but also a solution in which a reactant
is dissolved in an arbitrary solvent, an emulsion, a suspension, latex and
the like.
In particular, the method of the present invention is remarkably
advantageous in reactions in which two or more liquid substances are
reacted with each other to produce insoluble fine particles or an
emulsion. As described above, the inventive method can produce very fine
particles the size of submicrons by the high speed collision, and
particularly a dispersion in which the resulting insoluble fine particles
are dispersed in a solvent. Accordingly, the inventive method can produce
an extremely stable dispersion liquid and emulsion more easily.
Examples of reactions using the method of the present invention follow. It
is understood, however, that the present invention is not limited to these
reactions.
A reaction between an aqueous solution of CaCl.sub.2 and an aqueous
solution of NaCO.sub.3 to produce fine particles of CaCO.sub.3 ;
A reaction between an aqueous solution of BaCl.sub.2 and an aqueous
solution of NaCO.sub.3 to produce fine particles of BaCO.sub.3 ;
A reaction between an aqueous solution of BaCl.sub.2 and an aqueous
solution of H.sub.2 SO.sub.4 (or NaSO.sub.4) to produce fine particles of
BaSO.sub.4 ;
A reaction between an aqueous solution of ZnSO.sub.4 and an aqueous
solution of NaCO.sub.3 to produce fine particles of ZnCO.sub.3 ;
A reaction between an aqueous solution of ZnSO.sub.4 and an aqueous
solution of Na.sub.2 S.sub.x (or NH.sub.4 S.sub.x) to produce fine
particles of ZnS;
A reaction between an aqueous solution of Na.sub.2 O.multidot.3.3SiO.sub.2
and an aqueous solution of H.sub.2 SO.sub.4 to produce SiO.sub.2 in the
form of a sol; and
A reaction between an aqueous solution of ZnSO.sub.4 and an aqueous
solution of NaOH to produce fine particles of Zn(OH).sub.2. Fine particles
of ZnO are obtained by decomposing Zn(OH).sub.2 by heat.
The method of the present invention will be described in more detail by way
of examples. It is to be understood, however, that various changes and
modifications will be apparent to those skilled in the art. Therefore,
unless such changes and modifications depart from the scope of the present
invention, they should be construed as being included therein.
Using the reactor shown in FIG. 1, two substances were respectively
supplied at a specified speed through the inflow passages, and were
collided and reacted with each other at the joining portion. Reaction
product was discharged through the outflow passage. The particle diameter
of the reaction product was measured using a laser diffraction-type
particle size distribution measuring device "SALD-2000A" manufactured by
Shimazu Corporation. For comparison, another reaction was conducted using
a batch-type agitation table reactor "AM-9" manufactured by Nippon Seiki
Co., Ltd., and the particle diameter of the reaction product was measured
in the same manner. Both the two inflow passages for supplying substances
to the joining portion had a length of 7.5 mm and a diameter of 1.0 mm
(i.e., a sectional area of 3.93.times.10.sup.-7 m.sup.2). The outflow
passage for discharging reaction product from the joining portion had a
length of 15 mm and a diameter of 1.8 mm (i.e., a sectional area of
1,27.times.10.sup.-6 m.sup.2).
EXAMPLE 1
Relationship Between the Flow Rate and the Size of Produced Particle in the
Production of Barium Sulfate
Test samples:
barium chloride dihydrate (produced by Wako Pure Chemical Industries, Ltd.)
sodium sulfate (produced by Wako Pure Chemical Industries, Ltd.)
a surface active agent (a polycarboxylic acid-type surface active agent
manufactured by the Kao Corporation under the trademark "Demol EP")
pure water
Procedure of Test
(1) 18 weight percent of barium chloride aqueous solution and 9 weight
percent of sodium sulfate aqueous solution were respectively prepared.
(2) 300 g of the respective aqueous solutions prepared in step (1) were
diluted with pure water to 400 ml.
(3) The respective aqueous solutions prepared in step (2) were supplied
through the inflow passages under pressure, and were collided at the flow
rates shown in Table 1 to obtain a dispersion liquid containing dispersed
particles of barium sulfate.
(4) The surface active agent was dissolved in the sodium sulfate aqueous
solution in such a manner that its concentration is 0.1 weight percent in
the dispersion liquid after the reaction.
The test results are shown in Table 1 and FIG. 6. Specifically, at the flow
rate of less than 4 m/sec, the barium sulfate had an average particle
diameter as large as 3 .mu.m or larger. Contrary to this, at the flow rate
of 4 m/sec or higher, the average particle diameter was as small as about
1 .mu.m or smaller. At the flow rate of 7 m/sec or higher, the average
particle diameter was 0.5 .mu.m or smaller. At the flow rate of 15 m/sec
or higher, the average particle diameter was 0.2 .mu.m or smaller.
TABLE 1
Average 10% 90%
Flow particle particle particle
amount Flow rate diameter diameter diameter
(ml/min) (m/sec) (.mu.m) (.mu.m) (.mu.m)
25 1.1 4.18 0.36 32.16
50 2.1 3.39 0.29 12.89
100 4.2 1.13 0.23 4.21
200 8.5 0.36 0.16 1.04
300 12.7 0.29 0.11 0.44
400 17.0 0.14 0.06 0.27
500 21.2 0.12 0.05 0.20
600 25.5 0.07 0.03 0.15
700 29.7 0.04 0.02 0.13
EXAMPLE 2
Production of Barium Sulfate
Test samples:
barium chloride dihydrate (produced by Wako Pure Chemical Industries, Ltd.)
sodium sulfate (produced by Wako Pure Chemical Industries, Ltd.)
a surface active agent (a polycarboxylic acid-type surface active agent
manufactured by the Kao Corporation under the trademark "Demol EP")
pure water
Procedure of Test
A: Inventive method
(1) 18 weight percent of barium chloride aqueous solution and 12 weight
percent of sodium sulfate aqueous solution were respectively prepared.
(2) 300 g of the respective aqueous solutions prepared in step (1) were
diluted with pure water to 400 ml.
(3) The respective aqueous solutions prepared in step (2) were supplied
through the inflow passages under pressure, and were collided at the flow
rate of 25.5 m/sec or 600 ml/sec to obtain a dispersion liquid containing
dispersed particles of barium sulfate.
(4) The surface active agent was dissolved in the sodium sulfate aqueous
solution in such a manner that its concentration becomes 0.1 weight
percent in the dispersion liquid after the reaction.
B: Comparative method (batch-type agitation table reactor)
(1) 18 weight percent of barium chloride aqueous solution and 12 weight
percent of sodium sulfate aqueous solution were respectively prepared.
(2) 150 g of the respective aqueous solutions prepared in step (1) were
removed.
(3) 100 g of pure water was put in the reactor in which the respective
aqueous solutions removed in step (2) were simultaneously added into the
reactor while driving an agitator at 5000 r.p.m., and maintained with each
other for 30 minutes.
(4) The surface active agent was dissolved in the sodium sulfate aqueous
solution in such a manner that its concentration is 0.1 weight percent in
the dispersion liquid after the reaction.
The test results are shown in Table 2. It is found that the method of the
present invention can produce barium sulfate in the form of extremely fine
particles, as compared with the conventional batch-type agitation.
TABLE 2
10% diameter/
Median 90% diameter
Method diameter (.mu.m) (.mu.m)
Inventive 0.09 0.05/0.11
method
Comparative 1.06 0.39/2.53
method
EXAMPLE 3
Production of Barium Carbonate
Test samples:
barium chloride dihydrate (produced by Wako Pure Chemical Industries, Ltd.)
sodium carbonate (produced by Wako Pure Chemical Industries, Ltd.)
a surface active agent (a polycarboxylic acid-type surface active agent
manufactured by the Kao Corporation under the trademark "Demol EP")
pure water
Procedure of Test
A: Inventive method
(1) 18 weight percent of barium chloride aqueous solution and 9 weight
percent of sodium carbonate aqueous solution were respectively prepared.
(2) 300 g of the respective aqueous solutions prepared in step (1) were
diluted with pure water to 400 ml.
(3) The respective aqueous solutions prepared in step (2) were supplied
through the inflow passages under pressure, and were collided at the flow
rate of 25.5 m/sec or 600 ml/sec to obtain a dispersion liquid containing
dispersed particles of barium carbonate.
(4) The surface active agent was dissolved in the sodium carbonate aqueous
solution in such a manner that its concentration is 0.1 weight percent in
the dispersion liquid after the reaction.
B. Comparative method (batch-type agitation table reactor)
(1) 18 weight percent of barium chloride aqueous solution and 9 weight
percent of sodium carbonate aqueous solution were respectively prep area.
(2) 150 g of the respective aqueous solutions in step (1) were removed.
(3) 100 g of pure water was put in the reactor in which the respective
aqueous solutions removed in step (2) were simultaneously added into the
reactor while driving an agitator at 5000 r.p.m., and maintained with each
other for 30 minutes.
(4) The surface active agent was dissolved in the sodium carbonate aqueous
solution to a concentration of 0.1 weight percent in the dispersion liquid
after the reaction.
The test results are shown in Table 3. It is found that the method of the
present invention can produce barium carbonate in the form of extremely
fine particles, as compared with the conventional batch-type agitation.
TABLE 3
10% diameter/
Median 90% diameter
Method diameter (.mu.m) (.mu.m)
Inventive 0.19 0.13/0.28
method
Comparative 2.93 0.41/5.61
method
EXAMPLE 4
Production of Calcium Carbonate
Test samples:
calcium chloride dihydrate (produced by Wako Pure Chemical Industries,
Ltd.)
sodium carbonate (produced by Wako Pure Chemical Industries, Ltd.)
a surface active agent (a polycarboxylic acid-type surface active agent
manufactured by the Kao Corporation under the trademark "Demol EP")
pure water
Procedure of Test
A: Inventive method
(1) 16.5 weight percent of calcium chloride aqueous solution and 16 weight
percent of sodium carbonate aqueous solution were respectively prepared.
(2) 300 g of the respective aqueous solutions prepared in step (1) were
diluted with pure water to 400 ml.
(3) The respective aqueous solutions prepared in step (2) were supplied
through the inflow passages under pressure, and were collided at the flow
rate of 25.5 m/sec or 600 ml/sec to obtain a dispersion liquid containing
particles of calcium carbonate.
(4) The surface active agent was dissolved in the sodium carbonate aqueous
solution to a concentration of 0.1 weight percent in the dispersion liquid
after the reaction.
B: Comparative method (batch-type agitation table reactor)
(1) 18.5 weight percent of calcium chloride aqueous solution and 15 weight
percent of sodium carbonate aqueous solution were respectively prepared.
(2) 150 g of the respective aqueous solutions prepared in step (1) were
separated out.
(3) 100 g of pure water was put in the reactor in which the respective
aqueous solutions separated out in step (2) were simultaneously added into
the reactor while driving an agitator at 5000 r.p.m., and maintained with
each other for 40 minutes.
(4) The surface active agent was dissolved in the sodium carbonate aqueous
solution to a concentration of 0.1 weight percent in the dispersion liquid
after the reaction.
The test results are shown in Table 4. It is found that the method of the
present invention can produce calcium carbonate in the form of extremely
fine particles, as compared with the conventional batch-type agitation.
TABLE 4
10% diameter/
Median 90% diameter
Method diameter (.mu.m) (.mu.m)
Inventive 0.05 0.03/0.11
method
Comparative 0.26 0.09/2.01
method
EXAMPLE 5
Production of Zinc Sulfide
Test samples:
zinc sulfate heptahydrate (produced by Wako Pure Chemical Industries, Ltd.)
sodium sulfide (produced by Wako Pure Chemical Industries, Ltd.)
a surface active agent (a polycarboxylic acid type surface active agent
manufactured by the Kao Corporation under the trademark "Demol EP")
pure water
Procedure of Test
A: Inventive method
(1) 24 weight percent of zinc sulfate aqueous solution and 12 weight
percent of sodium sulfide aqueous solution were respectively prepared.
(2) 300 g of the respective aqueous solutions prepared in step (1) were
diluted with pure water to 400 ml.
(3) The respective aqueous solutions prepared in step (2) were supplied
through the inflow passages under pressure, and were collided at the flow
rate of 25.5 m/sec or 600 ml/sec to obtain a dispersion liquid containing
dispersed particles of zinc sulfide.
(4) The surface active agent was dissolved in the sodium sulfide aqueous
solution to a concentration of 0.1 weight percent in the dispersion liquid
after the reaction.
B: Comparative method (batch-type agitation table reactor)
(1) 24 weight percent of sodium sulfate aqueous solution and 12 weight
percent of sodium sulfide aqueous solution were respectively prepared.
(2) 150 g of the respective aqueous solutions prepared in step (1) were
separated out.
(3) 100 g of pure water was put in the reactor in which the respective
aqueous solutions separated out in step (2) were simultaneously added into
the reactor while driving an agitator at 5000 r.p.m., and maintained with
each other for 25 minutes.
(4) The surface active agent was dissolved in the sodium sulfide aqueous
solution to a concentration of 0.1 weight percent in the dispersion liquid
after the reaction
The test results are shown in Table 5. It is found that the method of the
present invention can produce zinc sulfide in the form of extremely fine
particles, as compared with the conventional batch-type agitation.
TABLE 5
10% diameter/
Median 90% diameter
Method diameter (.mu.m) (.mu.m)
Inventive 0.07 0.03/0.09
method
Comparative 1.40 0.31/4.52
method
EXAMPLE 6
Production of Zinc Hydroxide and Zinc Oxide
Test samples:
zinc sulfate heptahydrate (produced by Wako Pure Chemical Industries, Ltd.)
sodium hydroxide (produced by Wako Pure, Chemical Industries, Ltd.)
a surface active agent (a polycarboxylic acid-type surface active agent
manufactured by the Kao Corporation under the trademark "Demol EP")
pure water
Procedure of Test
A: Inventive method
(1) 24 weight percent of zinc sulfate aqueous solution and 12 weight
percent of sodium hydroxide aqueous solution were respectively prep area.
(2) 300 g of the respective aqueous solutions prepared in step (1) were
diluted with pure water to 400 ml.
(3) The respective aqueous solutions prepared in step (2) were supplied
through the inflow passages under pressure, and were collided at the flow
rate of 25.5 m/sec or 600 ml/sec to obtain a dispersion liquid containing
dispersed particles of calcium carbonate.
(4) The surface active agent was dissolved in the sodium hydroxide aqueous
solution to a concentration of 0.1 weight percent in the dispersion liquid
after the reaction.
B: Comparative method (batch-type agitation table reactor)
(1) 24 weight percent of zinc sulfate aqueous solution and 12 weight
percent of sodium hydroxide aqueous solution were respectively prepared.
(2) 150 g of the respective aqueous prepared in step (1) were separated
out.
(3) 100 g of pure water was put in the reactor in which the respective
aqueous solutions separated out in step (2) were simultaneously added into
the reactor while driving an agitator at 5000 r.p.m., and maintained with
each other for 30 minutes.
(4) The surface active agent was dissolved in the sodium hydroxide aqueous
solution to a concentration of 0.1 weight percent in the dispersion liquid
after the reaction.
The dispersion liquids produced by the inventive method and the comparative
method were respectively dried under a reduced pressure while being
agitated, and further dried at 120.degree. C. for one hour to obtain fine
particles of zinc oxide.
The size of the particles of zinc hydroxide contained in the dispersion
liquid and the size of the particles of zinc oxide obtained by the
heat-decomposition are shown in Table 6. It is found that the method of
the present invention can produce zinc hydroxide and zinc oxide in the
form of extremely fine particles, as compared with the conventional
batch-type agitation.
TABLE 6
10%
Median diameter/90%
diameter diameter
Method (.mu.m) (.mu.m)
Zinc Inventive 0.07 0.04/0.12
hydroxide method
Comparative 0.23 0.11/3.42
Method
Zinc oxide Inventive 0.05 0.03/0.10
method
Comparative 0.14 0.07/2.92
method
As described above, in the method of the present invention, two or more
substances having reactivity with each other are supplied through
different inflow passages to a joining portion. In the joining portion,
the substances are collided against each other at a flow rate of 4 m/sec
or higher to cause reaction with each other for a short time. Accordingly,
uniform reactions occur at high efficiency.
In the case of a reaction producing an insoluble reaction product, such as
fine particles, emulsion, or latex, the method of the present invention is
advantageous in that the high speed collision generates great collision
energy, and then turbulence and shearing forces, thus preventing
aggregation. In other words, the inventive method can produce a dispersion
liquid containing very fine particles the size of submicrons at a
remarkably high efficiency.
Further, the method of the present invention can maintain the reaction
system under constant conditions or avoid such physical and chemical
changes, such as variations in the amount and concentration of reactive
substances, or in pH.
Furthermore, the method of the present invention can provide sterilizing
effects because of the high speed collision.
Moreover, the reaction chamber where the high collision reaction occurs is
very small. Accordingly, the reaction temperature can be more easily and
accurately controlled by providing heating and cooling to the reaction
chamber.
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